Regulator system for generators



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April 27, 1954 Filed Feb. 5, 1953 WITNESSES:

J. T. CARLETON REGULATOR SYSTEM FOR GENERATORS Fig.|.

3 Sheets-Sheet l INVENTOR April 7, 1954 J. T. CARLETON 2,677,097REGULATOR SYSTEM FOR GENERATORS Filed Feb. 5, 1953 3 Sheets-Sheet 2Fig.3.

A E O a C (D (D 6 0) UI 2 a Time F' .4. L? lg l8 WITNESSES: INVENTORJysT orlton.

April 27, 1954 Filed Feb. 5, 1953 WITNESSES:

J. T. CARLETON REGULATOR SYSTEM FOR GENERATORS 3 Sheets-Sheet 3 INVENTORPatented Apr. 27, 1954 REGULATOR SYSTEM FOR GENERATORS James T.Carleton, Pittsburgh, Pa., assignor to Westinghouse ElectricCorporation, East Pittsburgh, Pa., a corporation of PennsylvaniaApplication February 5, 1953, Serial No. 335,372

Claims.

This invention relates to regulator systems and more particularly tomeans for stabilizing such regulator systems.

I-Ieretofore various means have been provided in order to stabilizeregulator systems. For in stance, a damping transformer is so connectedin the regulator system as to introduce a damp ing signal in the firststage of the regulator system. However, when saturable reactors or otherripple generating devices are utilized in the regulator system,considerable ripple voltage is also introduced into this first stage ofthe regulator system, which ripple voltage affects the operation of thefirst stage of the regulator system as well as subsequent stages. Thus,the regulating a tion of the regulator system is detrimentally affected.Not only is the operation of the regulator system detrimentally affectedby providing damping transformer for stabilizing purposes, but theoriginal cost of the damping transformer if oftentimes considerable.Further, in cases where the damping transformer is large in size itoccupies much needed space.

It is also old in the art to provide RC differentiating circuits inorder to stabilize regulator systems. However, when utilizing such RCdifferentiating circuits in a regulator system having incorporatedtherein saturable reactors or other ripple generating devices, a largeamount of ripple voltage is also introduced into the first stage of theregulator system with the-same detrimental eiiects as mentioned above.

An object of this invention is to provide for stabilizing a regulatorsystem having a sequence of stages of amplification, by inducing avoltage in a damping winding of one of the aforementioned stages ofamplification that is proportional to the derivative or rate of changeof the output voltage of this stage and by passing the current resultingfrom this induced voltage to a preceding aforementioned stage ofamplification so that such current flow produces a fiux that opposes thechange in fiux produced in this preceding stage by a sudden change inthe input to the aforementioned sequence of stages of amplication.

Another object of this invention is to provide for increasing theinitial speed of response of a regulator system having a sequence ofstages of amplification, by delaying the current induced in a dampingwinding of one of the aforementioned stages of amplification, theinduced current effecting a fiux in a preceding aforementioned stage ofamplification that opposes a change in the resultant flux in thispreceding stage of amplification.

A further object of this invention is to provide for stabilizing aregulator system having a sequence of amplification and to provide forimproving the regulating action of the system, by providing a push-pullsaturable reactor for one of the aforementioned stages so disposingdamping windings thereon that the combined or resultant ripple voltageinduced in the damping windings is negligible while the desiredresultant voltage of given polarity induced in the damping windingseffects a current flow to a preceding aforementioned stage ofamplification so that such current flow produces a flux which opposes achange in the resultant flux in this preceding stage of amplification.

Other objects of this invention will become apparent from the followingdescription when taken in conjunction with the accompanying drawings inwhich:

Figure 1 is a schematic diagram of circuits and apparatus illustratingan embodiment of the teachings of this invention;

Fig. 2 is a current delay network which can be substituted for thecurrent delay network illustrated in Fig. 1;

Fig. 3 is a graph illustrating the initial speed of response of theregulating systems illustrated in Figs. 1, 4 and 5 when certaincomponents are incorporated therein;

Fig. 4 is a schematic diagram illustrating another embodiment of theteachings of this invention; and

Fig. 5 is a schematic diagram illustrating still another embodiment ofthe teachings of this invention.

Referring to Fig. 1 of the drawings, this embodiment of the invention isillustrated with reference to a regulator system it for maintaining theoutput voltage of a direct current generator 12 substantially constant.In this instance, the generator [2 is provided with a field winding Mand an armature it which is disposed to supply energy to load conductorsl8 and 20.

In general, the regulator system it comprises two amplifiers or stagesof amplification, 22 and 24, the first stage of amplification 22being'responsive to the output voltage of the generator l2, and. thefield winding I4 of the generator l2 being responsive to the output ofthe last stage of amplification 24. As is well known in the art, theoutput voltage of the enerator i2 is compared with a reference voltage.In this instance the reference voltage is established a referencenetwork 2'l comprising a battery 2% and a variable resistor 29 connectedacross the battery 28. For purposes of simplifying the description ofthe operation of the regulator system it, it is that the amplifiers 22and 2G and the variable resistor 25) of the reference network 2'! are soadjusted that when the output voltage of the generator 12 is at itsregulated value the regulating signal to the first stage ofamplification 22 i of zero magnitude.

In this instance, the amplifier or first stage of amplification 22 is asaturable reactor and more particularly a magnetic amplifier or" theselfsaturating type. As can be seen from the drawings, the amplifier 22comprises two rectangular core members 39 and 32 constructed of magneticcore material. Load windings s4 and iii are disposed in inductiverelationship with the core members t ll and. respectively, and in orderto insure that current flows in only direction through the load windings34 and self-saturating rectifiers 33 and as are connected in seriescircuit relationship with the load windings 34 and 35, respectively.

For the purpose of obtaining a direct current output from the amplifiera iull-wave dry type rectifier 52 is connected in circuit relationshipwith the arm 2:1 7' 22 and with a suitable source of alternati g current(not shown) connected to the terminals it and M. In particu lar, theterminal id is connected to the junction point of the load windings 34and 3E and the junction point of the reotifiers 38 and ill is connectedto one of the input terminals of the rectifier E2. The other inputterminal of the rectifier G2 is connected to the terminal ea.

In this instance, biasing windings and 52 are disposed in inductiverelationship with the core members and. 32, respectively. As can be seenfrom the solid arrows associated with the biasing windings G and thesebiasing windings are so wound on their respective core members and. 32and so connected to terminals 53 and. for receiving a direct currentsource of energy (not shown) that current fiows through the biasingwindings 5i! and 52 to produce a flux in the core members 39 and 32,respectively, that opposes the flux produced by the current flow throughtheir respective load windings 34 and 36. As hereinbefore mentioned, theamplifier 22 is responsive to the output voltage of the generator I2.The amplifier 22 is rendered responsive to the output voltage or thegenerator l2 by disposing control windings 6i! and E2 in inductiverelationship with the core members 38 and 32, respectively. The controlwindings b2 and are connected in seri s circuit relationship with oneanother, one end of the series circuit being con nected to the positivete'minal of the generator I2 and the other end of the circuit beingconnected to the positive terminal of the battery 28. The negativeterminal of the generator i2 is connected to the variable resistor 29which can be adjusted to obtain the desired regulated output voltage forthe generator 22.

As illustrated, the amplifier 24 is also a sat urable reactor and moreparticularly a magnetic amplifier 0; the saturating type. The amplifier24 comprises rectangular core members "i and 16 which have disposed ininductive relationship therewith load windings l8 and 8'' respectively,and biasing windings 82 and 84, respectively. In

this instance the biasing windings t2 and 8 1 are likewise connected tothe terminals 55 and 58 and the biasing windings 82 and 86 are sodisposed on their respective core members l4 and 76 that current flowtherethrough produces a flux in the core members 14 and 76,respectively, that amplification. 24.

opposes the fiux produced by the current flow through the load windingsl3 and 82, respectively. Self-saturation is obtained by connectingselfsaturatin rectifiers 99 and ea in series circuit relationship withthe load windings l8 and 80, respectively.

In order to render the second stage of amplification 24 responsive tothe first stage of amplifi ation 22, control windings 93 ant 94 aredisposed in inductive relationship with the core members '14 and 75,respectively, the control windings and as being connected in ser'escircuit relationship across the output terminals of the rectifier 42. Asillustrated, a full-wave dry type rectifier ill is provided in order toobtain a direct current output from the second stage of amplification24. In particular, one of the input terminals of the rectifier S7 isconnected to the junction point of the self-saturating rectifier-s 9E;and. 12 and the junction point of the load windings l8 and so isconnected to the terminal 43. The other input terminal of the rectifierS1 is connected to the associated terminal 44. Further, the fieldwinding i l of the generator I2 is responsive to the direct currentoutput of the rectifier ill, one end of the field winding l4 beingconnected to one of the output terminals of the rectifier 9i and theother end of the field winding it being connected to the other outputterminal of the rectifier 91.

In accordance with the teachings of this invention, damping windings 96and 98 are disposed in inductive relationship with the core members "i4and lb, respectively, of the second stage of Likewise in accordance withthe teachings or this invention, control windings its and I02 aredisposed in inductive relationship with the core members 36 and 32,respectively, of the first stage of amplification 22. In particular, thedamping windings 98 and 98 of the amplifier 24 are connected in seriescircuit relationship with the control windings Hill and H32 of theamplifier 22 and with a current delay network EM, comprising a resistorHi6 and an inductance member 108, the function of which will bedescribed hereinafter. By interconnecting the damping windings 96 and 98of the second stage of amplification 24 with the control windings l00and H32 of the first stage of amplification 22, flux is established inthe core members and 32 of the first stage of amplification 22 on theoccurrence of a sudden change in the output voltage of the generator l2,which flux opposes the change in flux in the core members 30 and 32 asproduced by the current flow through the control windings SD and 62which are responsive to a result of the output voltage of the generatorl2, to thereby render the regulator system ll! stable.

The manner in which the damping windings 96 and 98 of the amplifier 24and the control Windings I03 and W2 of the amplifier 22 stabilize theregulator system Hi can be more clearly understood by a discussion ofthe operation of the regulator system iii. Assume for purposes ofdescription that the amplifiers 22 and 24 are so adjusted that when theoutput voltage of the generator 12 is at its regulated value, thecurrent flow through the control windings Ell and 62 of the amplifier 22is of zero magnitude. Assuming the output voltage of the generator 12suddenly increases, as may be caused by a reduction of load, to a valueabove its regulated value, current will flow through the controlwindings a d 52 of the amplifier 22 in such a direction value.

as to produce flux in the core members and 32 respectively, that opposesthe flux produced i these core members by the current flow through theload windings 3c and 36, respectively. Such an action decreases theoutput current from the first stage of amplification 22 and thusdecreases the magnitude of the current flow through the control windings9t and as of the second stage of amplification 2 3. The control windings93 and 94 of the second stage of amplification 25 are so disposed ontheir respective core members it and 76 that the decrease in fluxresulting from the decrease of current flow through the control windingsas and st effects a decrease in the output from the second stage ofamplification 2'4 and thus a decrease in the current flow through thefield winding 14 of the generator 2 to thereby return its output voltageto the regulated It is to be noted that with a sudden decrease in thecurrent fiow through the control windings 93 and 9-3, a voltage isinduced in the associated damping windings $16 and as, which isproportional to the derivative or rate of change of the output voltageof the second stage of amplification H, the induced voltage effecting acurrent flow from the damping windings 9d and 98 to the control windingsEtc and 32 of the first stage of amplification 22. The control windingsIEHJ and 562 are so disposed on their respective core members at and 32that this current now through them effects a flux in their respectivecore members 36 and 32 which opposes the increased flux produced in thecore members and 32 by the sudden, increase in the current flow throughthe control windings E512 and E52 01" the first stage of amplification.With the refer ence network Zl so adjusted that at the regulated outputvoltage of the generator i2 no current flows through the controlwindings cc and 52 of the amplifier 22, the direction of the flux in thecore members 3:! and 52 due to the current flow through the controlwindings til, E2, Ito and "32, when the output voltage of the generator12 suddenly increases to a. value above its regulated value, isindicated by the dotted arrows associated with these control windings.

On the other hand, assuming the output voltage of the generator itsuddenly decreases, as may be caused by an increase of load, to a valuebelow its regulated value, current will flow in such a direction throughthe control windings $0 and 62 of the first stage of amplification 22 asto produce fiux in their respective core members at and 32 in adirection as represented by the solid arrows associated therewith. Thisflux increases the output from the first stage of amplification 22 andthus increases the magnitude of the current flow through the controlwindings 93 and 9c of the second stage of amplification 24 to therebyincrease its output current to the field Winding M of the generator 52and thus return the output voltage of the generator it to the regulatedvalue. A sudden increase in the magnitude of the current flow throughthe control windings Q3 and 94 of the second stage of amplification itcauses a voltage to be induced in the damping windings lit and at, whichis proportional to the derivative or rate of change of the outputvoltage of the second stage of amplification 2 the induced voltageeffecting a current flow in such a direction through the controlwindings H39 and. E2 of the first stage of amplification 22 that flux isestablished in the core members 38 and 32, respectively, in a directionto oppose the flux produced in these core members 35! and 32,respectively, by the sudden decrease in the output voltage of thegenerator l2 below its regulated value. The direction of the flux in thecore members 32! and 32 as produced by the current flow through thecontrol windings tilt and 1232 of the first stage of amplification 22 asa result of the sudden decrease in the output voltage of the generatorI2 below its regulated value is represented by the solid arrowsassociated with the control windings Hi0 and H12.

As hereinbefore mentioned, a current delay network I04 is interconnectedwith the damping windings and 98 of the amplifier 24 and with thecontrol windings we and E2 of the amplifier 22. The function of thecurrent delay network its can be better understood by reference to Fig.3 of the drawings. For instance, assume it is desired to increase theregulated output voltage oi" the generator l2. This is accomplished byadjusting the variable resistor 29 of the reference network 2? in such adirection as to effect an unbalance between the output voltage of thegenerator [2 and the efiective voltage produced by the battery 28 so asto increase the output from both the first stage of amplification 22 andthe second stage of amplification 24 to thereby increase the currentfiow through the field winding I of the generator E2. The initial speedof response of the regulator system it when thus changing to a higherregulated output voltage for the generator i2 varies depending upon.what components are incorporated in the regulator system Iii. Forinstance, referring to Fig. 3, if the damping windings 98 and 98 of theamplifier 24 and the control windings it!) and H22 of the amplifier 22and the current delay network 804 are provided, the initial speed ofresponse of the regulator system i e is represented by a curve l ii]. Ifthe damping windings 98 and $33 and the control windings lcil and H52are provided and connected in series circuit relationship with oneanother, but the current delay network W4 is not provided, the initialspeed of response of the regulator system is as represented by a curveH2. On the other hand, if neither the damping windings cc and es, thecontrol windings 59D and H32, nor the current delay network EM areprovided, then the response of the regulator system is represented by acurve I M. By comparing the curves Hi3 and i 52 it is realized that byproviding the current delay network Hi4, the speed of response of theregulator system in is considerably increased. Of course, as can be seenfrom the curve I M, if neither the damping windings 96, $8, the controlwindings Hill, )2, nor the current delay network H35 are provided, theregulator system it is very unstable under such a change to a higherregulated output voltage for the generator I 2.

Referring to Fig. 2 of the drawings, there is illustrated a currentdelay network H6 which can be substituted for the current delay networkltd illustrated in Fig. l. The current delay network H5 can be connectedto the terminals H8, 420, l22 and it after having first removed theconductor 525 connected between the terminals H8 and i2 and the currentdelay network iii i connected between the terminals i2? and E24. Asillustrated, the current delay network Hi3 comprises the seriesconnected resistors I26 and i2? and the capacitor l28. When utilizingthe current delay network i it, the current delay iseffected by shuntingaportion of the current from the second stage of amplification 24through the capacitor E20.

Referring to Fig. l of the drawings, there is illustrated anotherembodiment of this invention in which like components of Figs. 1 and 4have been given the same reference characters. The main distinctionbetween the apparatus illustrated in Figs. 1 and -'l is that in theapparatus of Fig. 1 this invention is applied to two stages ofamplification, both of which stages comprise static components while inthe apparatus of Fig. 4 this invention is applied to two stages ofamplification, the first stage comprising static components and thesecond stage of amplification comprising rotating magnetic amplifier orexcitcr I 3%. In this instance, the rotating magnetic amplifier itsincludes an armature I32 which is disposed to supply direct current tothe field winding E4 of the generator 52, In order to provide aregulating signal for the generator I2, the rotating magnetic amplifierI30 is provided with a control winding I34 which is connected to theoutput terminals of the rectifier 42 to thereby render the controlwinding I34 responsive to changes in the output voltage of the generatorI2.

In accordance with the teachings of this invention the rotating magneticamplifier I30 is also provided. with a damping winding I30 which ismagnetically disposed with respect to the control winding :34 of theamplifier I30. ticular, the damping winding its and the control windingI34 are disposed on the pole pieces (not shown) of the rotating magneticamplifier I30. As illustrated, the damping winding I38 is con neoted inseries circuit relationship with the current delay network and with thecontrol windings I05 and 1102 of the first stage of amplification Thus,with a sudden increase or decrease in the output voltage of thegenerator I2, a voltage is induced in the damping winding I38 of therotating magnetic amplifier I30 proportional to the derivative of theoutput voltage of the amplifier which induced voltage effects a currentflow through the control windings I00 and I02 of the amplifier 22 insuch a direction as to produce a flux in the respective core members 3%and which flux opposes the change in flux in these core members 30 and32 as produced by a sudden increase or decrease in the output voltage ofthe generator I2.

When the damping winding I38 of the amplifier I30, the curr nt delaynetwork I04 and the control windings I09 and I02 of the first stage ofamplification 22 are provided, the initial speed of response of theregulator system illustrated in Fig. 4 is likewise represented by thecurve I III of Fig. 3. However, if the current delay network I04 asillustrated in Fig. 4 is omitted and the damping winding I38 isinterconnected with the control windings I60 and I02 oi the amplifier22, the initial speed of response of the regulator system is asrepresented by the curve II2. On the other hand, if the damping windingI38, the current delay network I04 and the control windings I06 and I02are omitted from th apparatus illustrated in Fig. 4-, the response ofthe regulator system is as illustrated by the curve II4.

It is to be understood that the current delay network I 10 illustratedin Fig. 2 can also be substituted for the current delay network I04illustrated in Fig. i by connecting it to the terminals H8, I20, I22,and I24. Since the damping winding I38, current delay network I04 andthe control windings I00 and H32 of the apparatus of Fig. 4 function inthe sam manner and pro- In parvide the same stabilizing effect as do thedamping windings 96, 98, the current delay network I04, and the controlwindings I00 and I02 of the apparatus of Fig. 1, a further descriptionof the apparatus of Fig. 4 is deemed unnecessary.

Referring to Fig. 5, this invention is illustrated as applied topush-pull saturable reactors 200 and 202, the saturable reactor 200constituting the first stage of amplification and the saturable reactor202 constituting the second stage of amplification. In particular, thesaturable reactors 200 and 202 are push-pull magnetic amplifiers of theself-saturating type and constitute the two stages of amplification fora regulator system 204 which maintains the output voltage of a directcurrent generator 206 substantially constant. In this instance, thegenerator 208 comprises a field winding divided into two sections 208and 2H) and an armature 2I2 connected to supply direct current energy toload conductors 2I4 and 2H5.

Referring more particularly to the push-pull magnetic amplifier 200,this amplifier comprises two main sections 220 and 222. The section 220comprises two rectangular core members 224 and 226 constructed ofmagnetic core material, while the section 222 comprises two rectangularcore members 228 and 230 constructed of magnetic core material.

In order to render the push-pull magnetic amplifier 200 responsive to achange in the output voltage of the generator 206, control windings 234,236, 238 and 240 are disposed in inductive relationship with the coremembers 224, 226, 228 and. 230, respectively. As can be seen from thedrawing, the control winding 234 is wound oppositely from the controlwinding 233 and the control winding 230 is wound oppositely from thecontrol winding 240 so that when the output voltage of one or thesections 220 or 222 increases, the output voltage of the other sectionwill decrease.

As illustrated, the control windings 234, 236, 238 and 240 are allconnected in series circuit relationship with one another, one end ofthe series circuit being connected to the load conductor 2I4 and theother end of the series circuit being connected through a voltagereference network 242 to the load conductor 2I6. As illustrated, thevoltage reference network 242 comprises a variable resistor 245 and abattery 248 connected across the variable resistor 246. The functioningof the voltage reference network 242 will be described hereinafter.

Load windings 250, 252, 254 and 256 are also disposed in inductiverelationship with the core members 224, 226, 220 and 230 respectively.Selfsaturation for the amplifier 200 is obtained by connectingself-saturating rectifiers 253, 250, 262, and 264 in series circuitrelationship with the load windings 250, 252, 254 and 256, respectively.For the purpose of supplying energy to the load windings 250, 252, 25and 256 of the amplifier 200, a potential transformer 210 is provided.In this instance, th potential transformer 210 comprises a primarywinding 212 which is connected to terminals 274 and 216 which in turnare connected to a suitable source of alternating current (not shown).The potential transformer 210 also comprises a secondary winding havingtwo sections 218 and 280.

In order to obtain a direct current voltage that is a measure of theoutput of the section 220 of the amplifier 200, a full-wave dry-typerectifier 282 is provided. In particular, one of the input terminals ofthe rectifier 282 is connected to one ammo-v 9. end or the section 218of the potential transformer 210 while the other end of the section 218is connected to the junction point of the load windings 250 and 252, thejunction point of the self-saturating rectifiers 258 and 260 beingconnected to the other input terminal of the rectifier 262.

On the other hand, to obtain a direct current voltage that is a measureof the output of the section 222 of'the amplifier 263, a full-wavedrytype rectifier 290 is provided. In particular, one of the inputterminals of the rectifier 296 is connected to one end of the windingsection 280 of the transformer 2'16. The other end of the section 283 isconnected to the junction point of the load windings 254 and 256 and thejunction point of the self-saturating rectifiers 262 and 264 isconnected to the other input terminal of the rectifier 268. Asillustrated, a resistor 232 is connected across the output terminals ofthe rectifier 282 and a resistor 26; is connected across the outputterminal of the rectifier 296, the resistors 292 and 294 being soconnected together that the resultant direct current voltage across theresistors 282 and 29 combined is a measure of the difference in theoutputs from the sections- 226 and 222 of the amplifier 2G6.

Biasing windings 366, 332, 334 and 366 are disposed in inductive.relationship with the core members 224, 226, 223 and 236, respectively.As illustrated, t e biasing windings 366, 302, 304- and 366 areconnected in series circuit relationship with one another, the seriescircuit being connected across a suitable direct current source 368--The biasing windings 3520, 332, 334 and 366 are so disposed on theirrespective core members that current flow through these biasing windingsproduces a flux. in the respective core members that opposes the fluxproduced by thecurrent flow through the associated load windings 256,-

252;, 254 and 256, respectively. This-can-bebet;

ter; seen by reference to the: solid arrows associated with thesevarious load and biasing windings;

Since the push-pull magnetic amplifier 262 in many respects isidentical. to the push-pull magnetic amplifier 256, like components ofthe am-' plifiers 296- and 282 have been given the same referencecharacter except that those like components of the amplifier 232' have aprime associated with the reference character. However, the directcurrent output voltages of the sections M2 and 31 of the amplifier 2G2are not com.- pared in the same way as the direct current outputvoltages of the sections 220 and 222 of the amplifier 233. Inparticular, the outputs of the sections 342 and 354 of the amplifier 292oppose one another in the field winding sections 266 and 219. of thegenerator 266. As illustrated, a fullwave dry-type rectifier 316 isprovided in order to obtain a direct current output from the section 312of the amplifier 232 while a full-wave: dry-type rectifier 3%8' isprovided in order to:

obtain a direct current output from the section 3M of the amplifier 222.As can be seen from the drawings, one of the input terminals of therectifier 356 is connected to the terminal 214 for receiving a suitablesource of alternating current (not shown). The other input terminal ofthe rectifier 316 is connected to the junction point of theselfsaturating rectifiers 2'58 and 260, the circuit to the load windings2.50 and 252' of the section 3l2 being completed by connecting thejunction point of these load Windings tothe terminal" 2'58. One of theinput ter- 1o" minals of the rectifier M8 is likewise connected to theterminal 214, the other input terminal of i the rectifier 358 beingconnected to the junction point of the self-saturating rectifiers 262and 264, the energizing circuit for the load windings 254 and 256' ofthe section 3 being completed by comiecting the junction point of theload windings 254' and 256" to the terminal 216.

In order to render the control windings 234', 235', 23-8 and 240' of thesecondstage of amplification 262 responsive to the direct current outputvoltage of the first stage of amplification 260, the control windings234-, 236', 238' and 243' are connected in series circuit relationshipwith one another, one end of the series circuit being connected to oneend of the resistor 294 and the other end of the series circuit beingconnected to one end of the resistor 292.

In accordance with the teachings of this invention, damping windings320, 322', 328 and 326 are disposed in inductive relationshi with thecore members 224', 226', 228 and 23a, respectively, of the second stageof amplification 202. Likewise, in accordance with the teachings of thisinvention, control windings 338', 332, 334 and 336 are disposed ininductive relationship with the core members 224, 226, 228 and 236,respectively, of the first stage of amplification 260. In order torender the control windings 336, 332r 334 and 336. of the first stage ofamplification 200 responsive to the currentinduced in the dampingwindings 323, 322,324 and 326 of the second stage of. amplification 202'when-there is a sudden change in the output. voltage-oi the generator266,, these damping; and control windings are with: the control;windings titan-332. 334; and: 336 I in order to delay,thecurrentr-induced in. the

damping windings 326,. 32232 1: and 326.

By providing the damping. windings 320, 322,

324- and 326,. and the control .wlndings'33s, 332,

336 and 336, and so disposing and interconnecting them as illustrated inFig; 5,. a very stable regulator system is provided.- In addition; by sodisposing the damping windings 323, 322,. 324 and 326 ontherespectivecore members of a push-pull saturable reactor such as the push-pullmagnetic amplifier 202, the ripple: flux produced in the core: members224', 226;, 228* and 238. by the ripple current flowing through the-loadwindings 252', 252', 254' and 256' respectively, does not affect theoperation of the regulator system1233. The: reason for this that theripple voltage induced in the damping windings 320', 322, 326 and 326 asa result of this ripple flux: in the core members 22- 225', 228' and236", respectively, is cancelled out since the ripple: voltage induced.in the damping. windings 328 and 322 of the section M2 is of oppositepolarity to that voltage induced in the damping windings 324 and 3255 ofthe section 3N of the second stage of amplification 262.

The manner in which the damping windings 326, 322, 324 and. 325 and thecontrol windings 339, 332;. 334 and 336 function to stabilizetheregulator system 20 can be better understood by considering theoperation of the regulator system 264. For'instance. assuming forpurposes 6' of description the variable resistor 245 of the referencenetwork'2-l2' is positioned as illustrated in fication 200, and theoutput voltage of the generator 206 is to be regulated for zero outputvoltage. Under such conditions the input current to the control windings234, 236, 238 and 240 of the first stage of amplification is of zeromagnitude and the input current to the control windings 234, 236', and238 and 240' is also of substantially zero magnitude. Therefore,whatever effect is produced by the field winding section 208 of thegenerator 206 is cancelled by the effect produced by the field windingsection 2l0 and thus the output voltage of the generator 206 remains atzero magnitude.

Assuming the output voltage of the generator 203 increases in thedirection as indicated by the polarity signs on the generator 206,current will how in such a direction through the control windings 234,236, 238 and 240 of the first stage of amplification 200, as to increasethe direct current output voltage of the section 222 of the amplifier200 and to decrease the direct current output voltage of the section220. With an increase in the direct current voltage across the resistor264, current flows in such a direction through the control windings 234,236, 238 and 240 of the second stage of amplification 202, that theoutput current of the section 3! of the second stage of amplification202 is increased and the output current of the section 3 l2 of theamplifier 202 is decreased, to thereby increase the current iiow throughthe field winding section 210 of the generator 206 and decrease thecurrent fiow through the field winding section 208 of the generator 206.The latter action returns the output voltage of the generator 206 to itsregulated value.

When the output voltage of the generator 206 suddenly increases in adirection as indicated by the polarity signs on the generator 206, avoltage is induced in the damping windings 320, 322, 324 and 326 of thesecond stage of amplification 202, which is proportional to thederivative or rate of change of the output voltage of the amplifier 202the induced voltage effecting a current flow through the controlwindings 330, 332, 334 and 336 of the first stage of amplification 200,that produces a flux in the core members 224, 22-6, 226 and 230,respectively, which opposes the flux produced in the core members 224,226, 228 and 230, respectively, by the increase in the current flow tothe control windings 234, 236, 238 and 240 of the first stage ofamplification 200. With such an increase in the output voltage of thegenerator 206, the direction of the fiux in the core members 224, 226,228 and 230 of the first stage of amplification 200 as produced by thecurrent flow through the control windings 234, 236, 238, 240, 330, 332,334 and 330, is as indicated by the dotted arrows associated with thesecontrol windings.

On the other hand, assuming the output voltage of the generator 206suddenly decreases to a value below its regulated output voltage ofsubstantially zero magnitude so that the polarity of the generator isopposite from that illustrated in Fig. 5, then the output current fromthe section 220 of the first stage of amplification 200 and the outputcurrent from the section 3| 2 of the second stage of amplification 202would increase and the output current from the section 222 of the firststage of amplification 200 and the output current from the section 314of the second stage of amplification 202 would decrease, to therebyincrease the current flow through the field winding section 208 of thegenerator 206 and decrease the current flow through the field windingsection 2!!) to thus return the output voltage of the generator 206 toits regulated value.

With such a sudden decrease in the output voltage of the generator 236below its regulated value, voltages are induced in the damping windings320, 322, 324 and 326 of the second stage of amplification 202 so as toefiect a current flow through the control windings 330, 332, 334 and 336of the first stage of amplification 200 in such a direction as toproduce a fiux that opposesthe fiux produced by the current flowthrough.

thecontrol windings 234, 236, 238 and 240 of the amplifier 200. Withsuch a sudden decrease in the output voltage of the generator 206 belowits regulated value, the direction of the flux in the core members 224,226, 228 and 230 as produced by the current flow through the controlwindings 234, 236, 238, 240, 330, 332, 334 and 336 is indicated by thesolid arrows associated with these control windings.

The eifect of adjusting the variable resistor 246 of the referencenetwork 242 in order to increase the output voltage of the generator 206to a value other than one of zero magnitude can also be seen byreferring to Fig. 3. The initial speed of response of the regulatorsystem 204 when moving to such a new value of output voltage for thegenerator 206 is as represented by the curve H0 assuming the dampingwindings 320, 322, 324 and 326 of the second stage of amplification 202,the control windings 330, 332, 334 and 336 of the first stage ofamplification" 200, and the current delay network 340 are provided. Ifthe current delay network 340 is omitted, and these damping windings320, 322, 324 and 326 and control windings 330, 332, 334 and 336 areprovided, the initial speed of response of the regulator system 204 isas indicated by the curve H2. However, if neither the damping windings320, 322, 324, 326, the control windings 330, 332, 334 and 336, nor thecurrent delay network 340 are provided, then the response of theregulator system 204 is as represented by the curve H4. Thus, when thecurrent delay network 340 and its interconnected control and dampingwindings are provided the regulator system is stable and it has a goodinitial speed of response. Since before adjusting the variable resistor246 of the reference network 242 it was assumed that the regulatorsystem 204 was adjusted so that the regulated output voltage ofgenerator 206 was substantially zero, the curves I 10, H2 and H4 shouldbe shifted vertically downwardly so as to start at zero output voltagefor the generator 206 in order to make the curves H0, H2 and H4 of Fig.3 truly representative in view or" the conditions assumed.

It is to be understood that although this invention has been describedwith reference to maintaining the output voltage of a direct currentgenerator substantially constant, this invention is applicable toregulator systems in general.

The apparatus involving the teachings of this invention has severaladvantages. For instance, the regulator systems illustrated in Figs. 1and 4 are very stable and have a good initial speed of response when theoutput voltage of their respective generators is changed to a newregulated value. In the apparatus illustrated in Fig. 5, theabove-mentioned advantages are obtained as well as the additionaladvantage of not having substantially any ripple current flowing fromthe damping windings 320, 322. 324 and 326 of 13 the second stage ofamplification 202 to the control windings sec, 332, 33:1 and 336 of thefirst stage of amplification zoo. By substantially reducing this ripplecurrent as is done in the apparatus illustrated in 5, a superiorregulating operation is obtained.

Since numerous changes may be made in the above-described apparatus andcircuits and different embodnents of the invention may be made withoutdeparting from the spirit and scope thereof, it is intended that all thematter contained in the foregoing description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense.

I claim as my invention:

1. In a regulator system, the combination comprising, a sequence ofstages of amplification for amplifying a regulating signal which effectsa restoration of a quantity to its regulated value, one of said stagesof aii olification comprising a control win and a ping winding disposedin inductive 1 .ationship with one another, an-

other of sale. a es of amplification that precedes sa t' '19 cl d oiamplification comprisin I T. the control stages of amplificaone to theoutput of said anof amplification and one of l g responsive to the 1, acurrent delay network conne: ed in c ill relationship with the dampingwinning with the other controi element of said another of said stages ofampli cations so as to the current flowing into said another controlelement, the damping winding being so magi sally disposed with respectto the control windin of one of stages of amplification that with asudden change the magnitude of the regulating signal a voltage irrducedin the damping winding proportional to the derivative of the output:voltage of said one of said stages of amplification, which inducedvoltage effects a current flow through other control element whichcurrent flow produces a signal in 'd another of said stages ofamplification in opposition the sudden change in the magnitude of theregulating signal.

2. In a regulator system, the combination comprising, a'sequence of sages of amplification for amplifying a regulating signal which eiiects arestoration of a quantity to its regulated value, one of stages ofamplification comprising a saturaoie reactor which includes magneticcore stages oi regulating si means, a control winding disposed ininductive I relationship with the magnetic core means and responsive tothe regulating signal, and a load winding disposed in inductiverelationship with the magnetic core means, another of said stages ofamplification subsequent to said one of said stages amplificationcomprising an amplifier having a damping winding and a control windingdisposed in inductive relationship with one another, circuit means forrendering the control winding of said amplifier responsive to themagnitude of the current fiOW through said lead winding when said loadWinding is connected to a suitable source of alternating current,another control winding disposed in inductive relationship with themagnetic core means of the saturable reactor, and a current delaynetwork connected in circuit relationship with said another controlwinding and with the damping winding of said amplifier, the dampingwinding .heing so. magnetically disposed with respect to the contrclwinding of said amplifier that with a sudden change in the magnitude ofthe current fiow through said control winding disposed in inductiverelationship with the magnetic core means and responsive to theregulating signal, a voltage is induced in the damping windingproportional to the derivative of the output voltage of said amplifier,which induced voltage effects a current flow through said anothercontrol winding which produces a flux in the magnetic core means of thesaturable reactor that opposes the change in flux produced by the suddenchange in the magnitude of the current flow through said control windingdisposed in inductive relationship with the magnetic core means andresponsive to the regulating signal.

3. In a regulator system, the combination comprising, a. sequence ofstages of amplification for amplifying a regulating signal which effectsa restoration of a quantity to its regulated value, one of said stagesof amplification comprising a saturable reactor which includes magneticcore means, a control winding disposed in inductive relationship withthe magnetic core means and responsive to the regulating signal, and aload winding disposed in inductive relationship with the magnetic coremeans, another of said stages of amplification subsequent to said one ofsaid stages of amplification comprising another saturable reactor havingmagnetic core means, a damping winding disposed in inductiverelationship with the magnetic core means of said another saturablereactor, a control winding disposed in inductive relationship with themagnetic core means of said another saturable reactor, a load windingdisposed in inductive relationship with the magnetic core means of saidanother saturable reactor, circuit means for rendering the controlwinding of said another reactor responsive to the magnitude of thecurrent flow through the load winding of said saturable reactor and forconnecting said lead windlugs to a suitable source of alternatingcurrent, another control winding disposed in inductive relationship withthe magnetic core means of said saturable reactor, and a current delaynetwork connected in circuit relationship with said another controlwinding and with said damping winding, said damping winding being somagnetically disposed with respect to the control winding of saidanother saturable reactor that with a sudden change in the magnitude ofthe current flow through the control winding of said saturable reactor avoltage is induced in said damping winding proportional to the derivatie of the output voltage of said another saturable reactor, which inducedvoltage effects a current flow through said another control windingwhich produces a flux in the magnetic core means of said saturablereactor that opposes the change in fiux produced by the sudden change inthe magnitude of the current flow through control winding of saidsaturable reactor.

4, In a regulator system, the combination comprising, a sequence ofstages of amplification for amplifying a regulating signal which effectsa restoration of a quantity to its regulated value, one of said stagesof amplification comprising a saturable reactor which includes magneticcore means, a control winding disposed in inductive relationship withthe magnetic core means and responsive to the regulating signal, a aload winding disposed in inductive relationship with the magnetic coremeans, another of said stages of amplification subsequent to said one ofsaid stages of amplification comprising a rotating magnetic amplifier,the rotating magnetic amplifier having a damping winding and a controlwinding disposed in inductive relationship with one another, circuitmeans for rendering the corn trol winding of the rotating magneticamplifier responsive to the magnitude of the current flow through saidload winding when said load winding is connected to a suitable source ofalternatin current, another control winding disposed in inductiverelationship with the magnetic core means of the saturable reactor, anda current delay network connected in circuit relationship with saidanother control winding and with said damping winding, said dampingwinding eing so magnetically disposed with respect to the controlwinding of the rotating magnetic ampliiier that with a sudden change inthe magnitude of the current flow through the control winding disposedin inductive relationship with the mag netic core means and responsiveto the regulating signal, a voltage is induced in the damping windingproportional to the derivative of the output voltage of the rotatingmagnetic ampliiier, which induced voltage effects a current how throughsaid another control winding which produces a in the magnetic core meansof the saturahle reactor that opposes the change in the flux produced bythe sudden change in the magnitude of the current flow through thecontrol winding disposed in inductive relationship the magnetic coremeans and responsive to the 'egulating signal.

5. In a regulating system for maintaining the output voltage of agenerator having a field winding substantially constant, the combinationcomprising, a saturable reactor including magnetic core means, a controlwinding disposed in induct ve relationship with the magnetic core meansand responsive to the output of the generator, and a load windingdisposed in inductive relationship with the magnetic core means, anothersaturable reactor having magnetic core means, a damping winding disposedin inductive relationship with the magnetic core means said anothersaturable reactor, a control winding disposed in inductive relationshipwith the mag netic core means of said another saturable reactor, a loadwinding disposed in inductive relationship with the magnetic core meansof said 7 another saturable reactor, circuit means for endering thecontrol winding of said another saturabie reactor responsive to themagnitude of the current flow through the load winding of said saturablereactor and for rendering the field winding of the generator responsiveto the magni tude of the current flow through the load wind ing of saidanother saturable reactor when said load windings are connected to asuitable source of alternating current, another control winding disposedin inductive relationship with the magnetic core means of said saturaolereactor, and a current delay network'comprising a resistor an inductancemember connected in series circuit relationship, the current delaynetwork being connected in circuit relationship with said anothercontrol winding and with said damping winding, said damping windingbeing so magnetically disposed with respect to the control winding ofsaid another saturable reactor that with a sudden change in the flux inthe magnetic core means or said another saturable reactor a voltage isinduced in said damping winding proportional to the derivative of theoutput voltage of said another saturable reactor, which induce voltageeffects a current flow through said another control Winding whichproduces a flux in the magnetic core means of said saturable reactorthat opposes the change in flux produced by change in the current flowthrough the control winding of said satura'ole reactor.

6. In a regulating system for maintaining the output voltage of agenerator having a field winding substantially constant, the combinationcomprising, a saturable reactor including magnetic core means, a controlwinding disposed in inductive relationship with the magnetic core meansand responsive to the output of the generator, and a load windingdisposed in inductive relationship with the magnetic core means, anothersaturalole reactor having magnetic core means, a damping windingdisposed in inductive relationship with the magnetic core means of saidanother saturable reactor, a control winding disposed in inductiverelationship with the magnetic core means oi said another saturable re--tcr, a load winding disposed in inductive relationship with themagnetic core means of said another saturable reactor, circuit means forrendering the control winding of said another saturacle reactorresponsive to the magnitude of the current flow through the load windingof said saturable reactor and for rendering the field winding of thegenerator responsive to the magni tude of the current flow through theload winding of said another saturable reactor when said load windingsare connected to a suitable source of alternating current, anothercontrol winding disposed in inductive relationship with the magneticcore means of said saturahlc reactor, and a current delay networkcomprising a resistor and a capacitor connected in series circuitrelationship across the damping winding, and another resistor connectedin series circuit relationship with the capacitor across said anothercontrol winding, said damping winding being so magnetically disposedwith respect to the control winding of said another saturahle reactorthat with a sudden change in the flux in the magnetic core means of saidanother saturable reactor a voltage is induced in said damping wind'ngproportional to the derivative of the output voltage of said anothersaturahle reactor, whicl'i induced voltage effects a current flowthrough said another control winding which produces a flux in themagnetic core means of said saturahle reactor that opposes the change influx produced by a change in the current flow through the controlwinding of said saturable reactor.

7. In a regulating for maintaining the output voltage of a generatorhaving a field winding substantially constant, the combination 7comprising, a saturahle reactor including magnetic core means, a controlwinding disposed in inductive relationship with the magnetic. core meansand responsive to the output oi he genorator, and a load windingdisposed in inductive relationship with th magnetic core means, arotating magnetic amplifier forsupplying energy to the field winding ofthe generator, the rotatniagnetic amplifier having a damping winding anda control disposed in inductive relationship with one another, circuitmeans for rendering the control winding of the rotating magneticamplifier responsive to the magnitude of the current flow through saidload winding when said load winding is connected to a suitable source ofalternating current, another control winding disposed in inductiverelationship with the magnetic core means of the saturable reactor, anda current delay network comprising a resistor and an inductance memberconnected in series circuit relationship, the current delay networkbeing connected in circuit relationship with said another controlwinding and with said damping winding, said damping winding being somagnetically disposed with respect to the control winding of therotating magnetic amplifier that with a sudden change in the magnitudeof the current flow through the control winding disposed in inductiverelationship with the magnetic core means and responsive to the outputof the generator a voltage is induced in the damping Windingproportional to the derivative of the output voltage of the rotatingmagnetic amplifier, which induced voltage effects a current flow throughsaid another control winding which produces a flux in the magnetic coremeans that opposes the change in flux produced by the sudden change inthe magnitude of the current flow through the control winding disposedin inductive relationship with the magnetic core means and responsive tothe output of the generator.

8. In a regulating system for maintaining the output voltage of agenerator having a field winding substantially constant, the combinationcomprising, a saturable reactor including magnetic core means, a controlwinding disposed in inductive relationship with the magnetic core meansand responsive to the output of the generator, and a load windingdisposed in inductive relationship with the magnetic core means, arotating magnetic amplifier for supplying energy to the field winding ofthe generator, the rotating magnetic amplifier having a damping windingand a control winding disposed in inductive relationship with oneanother, circuit means for rendering the control winding of the rotatingmagnetic amplifier responsive to the magnitude of the current flowthrough said load winding when said load winding is connected to asuitable source of alternating current, another control winding disposedin inductive relationship with the magnetic core means of the saturablereactor, and a current delay network comprising a resistor and acapacitor connected in series circuit relationship across the dampingwinding, and another resistor connected in series circuit relationshipwith the capacitor across said another control winding, said dampingwinding being so magnetically disposed with respect to the controlwinding of the rotating magnetic amplifier that with a sudden change inthe magnitude of the current flow through the control winding disposedin inductive relationship with the magnetic core means and responsive tothe output of the generator a voltage is induced in the damping windingproportional to the derivative of the output voltage of the rotatingmagnetic amplifier, which induced voltage effects a current flow throughsaid another control winding which produces a flux in the magnetic coremeans that opposes the change in flux produced by the sudden change inthe magnitude of the current fiow through the control winding disposedin inductive relationship with the magnetic core means and responsive tothe output of the generator.

9. In a regulating system for maintaining the output voltage of agenerator having a field winding substantially constant, the combinationcomprising, an amplifier of the saturable reactor type includingmagnetic core means and a control winding disposed in inductiverelationship with the magnetic core means and responsive to the outputof the generator, a push-pull saturable reactor having two sections, thefield winding of the generator being responsive to the output of the twosections of the push-pull saturable reactor, each section of thepush-pull saturable reactor including at least one control winding andone damping winding disposed in inductive relationship with one another,circuit means for rendering the control windings of the pushpullsaturable reactor responsive to the output of said amplifier, anothercontrol winding disposed in inductive relationship with the magneticcore means of said amplifier, and circuit means for connecting a currentdelay network in circuit relationship with said another control windingand with the damping windings of the push-pull saturable reactor, thedamping windings being so disposed that with a sudden change in themagnitude of the current flow through the control winding of saidamplifier a voltage is induced in the damping windings proportional tothe derivative of the output voltage of the pushpull saturable reactor,which induced voltage effects a current fiow through said anothercontrol winding which produces a flux in said magnetic core means thatopposes the change in flux produced by the sudden change in themagnitude of the current flow through the control winding of saidamplifier.

10. In a regulating system for maintaing the output voltage of agenerator having a field winding substantially constant, the combinationcomprising, a first stage push-pull saturable reactor having twosections, each section of the first stage push-pull saturable reactorincluding magnetic core means and a control winding responsive to theoutput of the generator and disposed in inductive relationship with therespective magnetic core means, a second stage push-pull saturablereactor having two sections, the field winding of the generator beingresponsive to the outputs of the two sections of the second stagesaturable reactor, each section of the second stage push-pull saturablereactor including magnetic core means and a damping winding and acontrol winding disposed in inductive relationship with their respectivemagnetic core means, circuit means for rendering the control windings ofthe second stage push-pull saturable reactor responsive to the output ofthe first stage push-pull saturable reactor, another control Windingdisposed in inductive relationship with each of the magnetic core meansof the first stage push-pull saturable reactor, and circuit means forconnecting a current delay network in circuit relationship with saidanother control winding and with the damping windings of the secondstage push-pull saturable reactor, the damping windings being sodisposed that with a sudden change in the magnitude of the current flowthrough the control windings of the first stage push-pull saturablereactor a voltage is induced in the damping windings proportional to thederivative of the output voltage of the second stage push-pull saturablereactor, which induced voltage effects a current flow through saidanother control winding which produces a flux in the respective magneticcore means of the first stage push-pull saturable reactor that opposesthe change in flux produced by the sudden change in the magnitude of thecurrent flow through the control windings of the first stage push-pullsaturable reactor.

No references cited.

